[ ir-i-vur-suh-buh l ]
/ ˌɪr ɪˈvɜr sə bəl /


not reversible; incapable of being changed: His refusal is irreversible.

Origin of irreversible

First recorded in 1620–30; ir-2 + reversible

OTHER WORDS FROM irreversible

ir·re·vers·i·bil·i·ty, ir·re·vers·i·ble·ness, nounir·re·vers·i·bly, adverb Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for irreversible

British Dictionary definitions for irreversible

/ (ˌɪrɪˈvɜːsəbəl) /


not able to be reversedthe irreversible flow of time
not able to be revoked or repealed; irrevocable
chem physics capable of changing or producing a change in one direction onlyan irreversible reaction
thermodynamics (of a change, process, etc) occurring through a number of intermediate states that are not all in thermodynamic equilibrium

Derived forms of irreversible

irreversibility or irreversibleness, nounirreversibly, adverb
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012